BACKBONE
backbone
(noun) the part of a network that connects other networks together; “the backbone is the part of a communication network that carries the heaviest traffic”
spine, backbone
(noun) the part of a book’s cover that encloses the inner side of the book’s pages and that faces outward when the book is shelved; “the title and author were printed on the spine of the book”
backbone, grit, guts, moxie, sand, gumption
(noun) fortitude and determination; “he didn’t have the guts to try it”
anchor, mainstay, keystone, backbone, linchpin, lynchpin
(noun) a central cohesive source of support and stability; “faith is his anchor”; “the keystone of campaign reform was the ban on soft money”; “he is the linchpin of this firm”
Source: WordNet® 3.1
Etymology
Noun
backbone (countable and uncountable, plural backbones)
The series of vertebrae, separated by disks, that encloses and protects the spinal cord, and runs down the middle of the back in vertebrate animals.
(figuratively) Any fundamental support, structure, or infrastructure.
(figuratively) Courage, fortitude, or strength.
Synonyms
• spine
• spinal column
• vertebral column
• See also backbone
Source: Wiktionary
Back"bone", n. Etym: [2d back,n.+ bone. ]
1. The column of bones in the back which sustains and gives firmness
to the frame; the spine; the vertebral or spinal column.
2. Anything like , or serving the purpose of, a backbone.
The lofty mountains on the north side compose the granitic axis, or
backbone of the country. Darwin.
We have now come to the backbone of our subject. Earle.
3. Firmness; moral principle; steadfastness.
Shelley's thought never had any backbone. Shairp.
To the backbone, through and through; thoroughly; entirely. "Staunch
to the backbone." Lord Lytton.
Source: Webster’s Unabridged Dictionary 1913 Edition